Thermoformed Tray for Food Products

ABSTRACT

Thermoformed trays comprising ribs retain individual food products in place. The individual food products are generally elongate and prone to displacement during handling. The formed trays comprise: a base; a plurality of sidewalls integrally formed with and extending from the base, the base and sidewalls defining an interior cavity having a cavity width; a plurality of pairs of ribs integrally formed with and extending from first and second opposing sidewalls into the interior cavity, and a plurality of channels positioned between and separating adjacent ribs, wherein each channel of an adjacent pair of ribs defines an individual food product receiving slot. Each rib may extend into the interior cavity a length that is at least about 7% of the cavity width.

TECHNICAL FIELD

The present disclosure relates generally to packaging for food products including a formed tray that holds individual food products in place when the tray is tilted for display relative to its flat orientation during packing, shipment, and storage.

BACKGROUND

Food packaging keeps food fresh and protected until its preparation and consumption. Some food packaging allows consumers to view the food prior to purchase. Suitable packages for fresh foods such as meats can be a combination of a clear film and a thermoformed tray, which allows for viewing of the food. The tray can provide structure to the package such that many packages can be handled shipped, and stored efficiently. The clear film can provide barrier properties such as oxygen and moisture protection while allowing the package contents to be seen. Consumers may overlook packages on display if there is an unfavorable product appearance and/or if the package contents are not orderly, despite the food itself remaining fresh and protected, which can lead to waste.

For example, cylindrical products such as sausage links that are stored in trays having no internal features can roll around during handling and shipment, and upon display. This can result in the products contacting each other and the clear film, which can impact perception of the products by consumers.

There is a need for packages that display food in a favorable and orderly way while utilizing packaging materials in an efficient and cost-effective manner.

SUMMARY

Provided are formed trays and food packages utilizing the same that are suitable for storing and displaying food in a favorable and orderly way while utilizing packaging materials in an efficient and cost-effective manner.

A first aspect is a formed tray for packing food products, the tray comprising: a base; a plurality of sidewalls integrally formed with and extending from the base, the base and sidewalls defining an interior cavity having a cavity width; a plurality of pairs of ribs integrally formed with and extending from first and second opposing sidewalls into the interior cavity, and a plurality of channels positioned between and separating adjacent ribs, wherein each channel of an adjacent pair of ribs defines an individual food product receiving slot.

Each rib may extend into the interior cavity a length that is at least about 7% of the cavity width.

Each pair of ribs may be effective to retain an individual food product in the individual food product receiving slot upon movement of the tray from a first position to a second position, the second position being greater than or equal to about 45° more upright than the first position.

In one or more embodiments, each rib comprises a food contacting face, a secondary face opposing the food contacting face, and a fluted edge at an intersection of the food contacting and secondary faces. The fluted edge of each rib may be disposed at an angle α relative to an interior surface of the base, and about 180°≥α≥90°. Each food contacting face may be disposed at an angle Θ₁ relative to the sidewall from which the rib extends and about 135°≥Θ₁≥45° and each secondary face is disposed at an angle Θ₂ relative to the sidewall from which the rib extends and about 135°≥Θ₂≥45°.

The interior cavity may have a depth “D” that is 1.1 to 3.0 times greater than a diameter or thickness of an individual food product.

The formed tray may further comprise third and fourth opposing sidewalls.

The interior surface may be free of protrusions apart from the ribs. The interior surface may be free of any added feature that would retain a plurality of individual food products packaged in the tray.

Another embodiment is a formed tray for packing food products, the tray comprising: a base; a plurality of sidewalls integrally formed with and extending from the base, the base and sidewalls defining an interior cavity having a cavity width, the plurality of sidewalls comprising first and second sets of opposing sidewalls; a plurality of pairs of ribs integrally formed with and extending from the first set of opposing sidewalls into the interior cavity, and a plurality of channels positioned between and separating adjacent ribs, wherein each channel of an adjacent pair of ribs defines an individual food product receiving slot; wherein each rib comprises a food contacting face, a secondary face opposing the food contacting face, and a fluted edge at an intersection of the food contacting and secondary faces.

Each rib may extend into the interior cavity a length that is at least about 7% of the cavity width.

Each food contacting face may be disposed at an angle Θ₁ relative to the sidewall from which the rib extends and about 135°≥Θ₁≥45° and each secondary face is disposed at an angle Θ₂ relative to the sidewall from which the rib extends and about 135≥Θ₂≥45′.

Another aspect is a food package comprising: one or more formed trays disclosed herein; and a lidding film sealing food products in the interior cavity by a heat seal. The food products may be elongate. The food products may be cylindrically-shaped.

The food package may comprise two formed trays joined along edges of flanges of the trays.

Another aspect is a method of packaging food comprising: thermoforming a tray according to any tray disclosed herein; and sealing foods in the interior cavity of the tray with a lidding film.

In a further aspect, a method of displaying food products comprises: obtaining any food package disclosed herein; and tilting the package from a first position to a second position, the second position being greater than or equal to about 45° more upright than the first position. Individual food products are retained in the individual food product receiving slots upon tilting.

These and other aspects of the invention are described in the detailed description below. In no event should the above summary be construed as a limitation on the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings, in which:

FIG. 1 is an exploded perspective view of an exemplary food package according to an embodiment;

FIG. 2 is a bottom view of a tray;

FIG. 3 is a top view of an interior cavity of a tray;

FIGS. 3A-3B are close-up views of exemplary ribs and portion of a sidewall;

FIG. 4 provides exemplary shapes for fluted surfaces;

FIGS. 5-8 are schematics of various rib shapes holding food product in place;

FIG. 9 is a cross-section view of the tray of FIG. 3 along line 9-9;

FIG. 10 is a perspective side view of a package according to an embodiment;

FIGS. 11A-11B are photographs of a tray, top view and side view, according to an embodiment of a tray holding sausages in a first position flat on a horizontal surface;

FIGS. 12A-12B are photographs of the tray of FIGS. 11A-11B, front view and side view, upon movement of the tray to a section position that is about 45° more upright than the first position;

FIGS. 13A-13B are photographs of the tray of FIGS. 11A-11B, front view and side view, upon movement of the tray to a section position that is about 90° more upright than the first position;

FIG. 14 is a photograph of a top view of a comparative tray holding sausages in a first position flat on a horizontal surface; and

FIGS. 15A-15B are photographs of the tray of FIG. 14, front view and side view, upon movement of the tray to a section position that is about 75° more upright than the first position.

The figures are not necessarily to scale. Like numbers used in the figures refer to like components. It will be understood, however, that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

DETAILED DESCRIPTION

Packages of the present disclosure display food in a favorable and orderly way while utilizing packaging materials and methods that are efficient and cost-effective. In particular, thermoformed trays are designed to retain individual food products in place. The individual food products are generally elongate and prone to displacement during handling.

Reference to “elongate” means a shape that has a length that is larger than its diameter by an order of magnitude or more. Elongate food products may be cylindrically-shaped, having a round cross-section, for example, sausages, hot dogs, and the like. Elongate food products may have a square or rectangular cross-section, for example, wafer cookies.

“Individual food product receiving slots” refer to a feature of the tray that retains an individual food product in a spaced relation from another individual food product. In one or more embodiments, the individual food product receiving slots are designed to specific dimensions of the food product to be packaged. In one or more embodiments, the individual food product receiving slots are designed to reduce or eliminate or substantially eliminate contact between individual food products. In one or more embodiments, the individual food product receiving slots reduce or eliminate or substantially eliminate contact between the individual food products and lidding film of the package. While an individual food product receiving slot may be designed to retain a single food product, it is understood that an individual food product receiving slot may receive one or more individual food products that may stay in place upon movement of the tray.

As used in this disclosure, the term “sheet” refers to a plastic web having a thickness of at least about 0.254 mm (10 mil). The term “film” means a plastic web of any thickness and is not limited to a plastic web having a thickness of less than about 0.254 mm (10 mil). In one preferred embodiment, the sheet of the present invention has a thickness of between 0.254 mm and 1.27 mm (10 mil and 50 mil). In other preferred embodiments, the sheet of the present invention has a thickness of between 0.381 mm and 1.143 mm (15 mil and 45 mil) or between 0.508 mm and 0.762 mm (20 mil and 30 mil).

As used herein, the terms “thermoformable” and “thermoformed” refer to monolayer or multilayer thermoplastic polymer sheets, films or webs having sufficient rigidity or stiffness to be formed into a desired shape by the application of a differential pressure between the film or sheet and a mold, by the application of heat, by the combination of heat and the application of a differential pressure between the film or sheet and a mold, or by any thermoforming technique known to those skilled in the art. For purposes of this application, the term “thermoformable” also refers to non-oriented monolayer or multilayer thermoplastic polymer sheets, films or webs having a thickness of at least 10 mil.

Tray Materials

Formed trays herein comprise a material suitable for thermoforming. Generally, non-oriented monolayer or multilayer thermoplastic polymer sheets, films or webs having a thickness of at least 10 mil may be used. Suitable materials for the polymer sheets, films or webs as a structural layer include but are not limited to: crystalline polyester (CPET), amorphous polyester (APET), polypropylene (PP), high impact polystyrene (HIPS), and polyvinyl chloride (PVC).

The formed trays may be formed from a multilayer thermoplastic polymer sheet comprising the structural layer and one or more barrier layers laminated or adhered thereto. Exemplary barrier layers include oxygen and/or moisture barrier layers. Suitable oxygen barrier layers can comprise an ethylene vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), polyamide, polyester, polyalkylene carbonate, polyacrylonitrile, as known to those of skill in the art. Suitable moisture barrier layers include PVDC, or polyolefins such as LOPE or LLDPE.

Lidding Film

The lidding film may comprise a film of one or more layers including but not limited to a sealing layer, one or more barrier layers, one or more adhesive or tie layers, which may include one or more tie layers, and an exterior protective layer. A “layer” as used herein refers to a building block of a film that is a structure of a single polymer-type or a blend of polymers or that may have an additive.

The sealing layer is one that seals to form a hermetic seal. That is, the sealing layer comprises a thermoplastic polymer or polymer mixture that softens when exposed to heat and returns to its original condition when cooled to room temperature. The sealing layer may be used for bonding, at adjacent bonding surfaces, with a base material to form a peripheral seal, normally by heat sealing. The base material may be a rigid or flexible thermoformed tray. The base material may be a film of the same type or of a different type as the lidding film. In general, the sealing layer may comprise any suitable thermoplastic material including, but not limited to, synthetic polymers such as polyesters, polyamides, polyolefins, polystyrenes, and the like. Thermoplastic materials may also include any synthetic polymers that are cross-linked by either radiation or chemical reaction during a manufacturing or post-manufacturing process operation. Exemplary polyolefins include polyethylene (PE) and polypropylene (PP).

One or more barrier layers function as a gas barrier layer and/or as a moisture barrier layer. An oxygen barrier is preferably selected to provide an oxygen permeability sufficiently diminished to protect the packaged article from undesirable deterioration or oxidative processes. A moisture barrier is preferably selected to provide a moisture permeability sufficiently dimensioned to protect the packaged article from undesirable deterioration. A barrier layer can comprise any suitable material. An oxygen barrier layer can comprise an ethylene vinyl alcohol copolymer (EVOH), polyvinylidene chloride (PVDC), polyimide, polyester, polyalkylene carbonate, polyacrylonitrile, as known to those of skill in the art. Suitable moisture barrier layers include PVDC, or polyolefins such as LOPE or LLDPE. It is desirable that the thickness of the barrier layer be selected to provide the desired combination of the performance properties sought e.g. with respect to oxygen permeability, and delamination resistance, and water barrier properties. Suitable thicknesses in multilayer films are less than 15%, e.g. from 3 to 13% of the total film thickness and preferably less than about 10% of the total thickness of the multilayer film.

An adhesive or tie layer is a material placed on one or more other layers, partially or entirely, to promote the adhesion of that layer to another surface. Preferably, adhesive layers or coatings are positioned between two layers of a multilayer film to maintain the two layers in position relative to each other and prevent undesirable delamination. Unless otherwise indicated, a tie layer or an adhesive layer or coating can have any suitable composition that provides a desired level of adhesion with the one or more surfaces in contact with the adhesive layer material. Optionally, a tie layer or an adhesive layer or coating placed between a first layer and a second layer in a multilayer film may comprise components of both the first layer and the second layer to promote simultaneous adhesion of the adhesive layer to both the first layer and the second layer to opposite sides of the adhesive layer.

The exterior protective layer is seen by the user/consumer and preferably has desirable optical properties and may preferably have high gloss. Also, it preferably withstands contact with sharp objects and provides abrasion resistance, and for these reasons it is often termed the abuse resistant or protective layer. This exterior protective layer may or may not also be used as a heat sealable layer. As the exterior surface layer of the film, this layer most often is subject to handling and abuse e.g. from equipment during packaging, and from rubbing against other packages and shipping containers and storage shelves during transport and storage. This contact causes abrasive forces, stresses and pressures which may abrade away the film causing defects to printing, diminished optical characteristics or even punctures or breaches in the integrity of the package. Therefore the exterior surface layer is typically made from materials chosen to be resistant to abrasive and puncture forces and other stresses and abuse which the packaging may encounter during use. A preferred exterior layer comprises a polyester film, preferably polyester terephthalate, which is preferably at least 0.9 mil (22.9 micrometer) in thickness. Suitable exterior surface layers may comprise: oriented polyester, amorphous polyester, polyamide, polyolefin, cast or oriented nylon, polypropylene, or copolymers, or blends thereof. Oriented films of this or any other layer may be either uni-axially or bi-axially oriented. The exterior layer thickness is typically about 0.5 (12.7 micrometer) to about 2.0 mil (50.8 micrometer). Thinner layers may be less effective for abuse resistance, however thicker layers, though more expensive, may advantageously be used to produce films having unique highly desirable puncture resistance and/or abuse resistance properties.

Fabrication

In general terms, to form the trays disclosed herein, thermoforming is used. In the simplest form, thermoforming is the draping of a softened sheet over a shaped mold. In the more advanced form, thermoforming is the automatic high speed positioning, of a sheet having an accurately controlled temperature into a pneumatically actuated forming station whereby the article's shape is defined by the mold, followed by trimming and regrind collection as is well known in the art. Still other alternative arrangements include the use of drape, vacuum, pressure, free blowing, matched die, billow drape, vacuum snap-back, billow vacuum, plug assist vacuum, reverse draw with plug assist, pressure bubble immersion, trapped sheet, slip, diaphragm, twin-sheet cut sheet, twin-sheet roll-fed forming or any suitable combinations of the above.

Before describing several exemplary embodiments of the invention, it is to be understood that the invention is not, limited to the details of construction or process steps set forth in the following description. The invention is capable of other embodiments and of being practiced or being carried out in various ways.

Turning to the figures, FIG. 1 is an exploded perspective view of an exemplary food package 100 having a lidding film 102 and a tray 104; FIG. 2 is a bottom view of the tray 104; and FIG. 3 is a top view of the interior cavity 136 of the tray. The lidding film 102 is a barrier film of suitable composition and layer(s) to provide desired freshness and protection according to the type of food product to be, packaged. The lidding film 102 is generally clear to allow for the contents of the package 100 to be viewed and optionally comprises indicia regarding details about the product and brand and the like. A portion of the lidding film 102 is heat-sealed to a sealing surface 106 of a flange 137 of the tray 104 thereby covering and sealing an interior cavity 136 by a heat seal. The term “heat seal” refers to welding or melting of two polymeric surfaces together by the application of heat and pressure. It will be appreciated by those skilled in the art that heat seals are hermetic seals meaning that they prevent the ingress of air and/or moisture through the seal. The tray 104 is a formed tray, in other words, it is thermoformed. The lidding film 102 may be thermoformed, otherwise formed, or may be unformed. In use, removal of the lidding film 102 from the tray 104 is achieved by peelably tearing the lidding film 102 away from tray 104 whereby the heat seal is broken.

The tray has a base 122 having an interior surface 124 and an exterior surface 126. The interior surface 124 is free of protrusions apart from the ribs. The interior surface 124 is free of any added feature that would retain an individual food product upon packaging of the individual food product in an individual food product receiving slot. That is, there are not any spikes or protrusions or ridges or the like that could provide a way to keep food product in place. The tray also has sidewalls 128, 130, 132, 134 integrally formed with and extending from the base 122. Sidewalls 128 and 132 are a first set of opposing sidewalls. Sidewalls 130 and 134 are a second set of opposing sidewalls. The base 122 and sidewalls 128, 130, 132, 134 define, the interior cavity 136, which has a first cavity edge 108 a and a second cavity edge 108 b. Pairs of ribs 110 a,b; 112 a,b; 114 a,b; and 116 a,b; 118 a,b; 120 a,b are integrally formed with the first set of opposing sidewalls, namely first and second sidewalls 128 and 132, extending into the interior cavity 136.

For exemplary purposes, the tray 104 demonstrates two sizes of ribs. Pairs of ribs 110 a,b; 112 a,b; and 114 a,b are a first length from the sidewalls from which they extend. Pairs of ribs 116 a,b; 118 a,b; and 120 a,b are a second length from the sidewalls from which they extend. Ribs of trays are sized to accommodate a food product for packaging. Within a pair, ribs are usually the same size. Various pairs of ribs may all be of the same length or they may be designed for differing lengths depending on the application with respect to, for example, the food product and the display configuration.

With detailed reference to FIGS. 3 and 3A-3B, width “W” of the interior cavity 136 extends from the first cavity edge 108 a to the second cavity edge 108 b. Ribs 110 a,b; 112 a,b; and 114 a,b each extend a length L₁(a); L₁(b), respectively, into the interior cavity. Ribs 116 a,b; 118 a,b and 120 a,b each extend a length L₂(a); L₂(b), respectively, from the respective sidewall/edge of cavity 108 a, 108 b into the interior cavity. In one or more embodiments, each rib extends into the interior cavity a distance that is at least 7% of the width or at least 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, 20%, or 25% or more, and all values and subranges therebetween. As such, because there are pairs of ribs, approximately 14% of the width “W”, or more provides support to a food product in order to retain the food product upon tilting the tray from a first horizontal position to a second tilted position. In one or more embodiments, the percent of the width “W” that provides support to a food product is at least 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 40%, or 50% or more, and all values and subranges therebetween. In one or more embodiments, “W” is 0.1-2 centimeters greater than the longest portion of the product.

Each rib, 110 a,b; 112 a,b; 114 a,b; 116 a,b; 118 a,b; 120 a,b has a food contacting face 138, a secondary face 140 opposing the food contacting face 138, and a fluted edge 139 at an intersection of the food contacting and secondary faces. Between a food contacting face of one rib and a secondary face of an adjacent rib is a spacing (“S”) of the channel 142. S is generally greater than the diameter or height of the food product by about 0.1 tot centimeters. There are a plurality of channels 142 positioned between and separating adjacent ribs. The channels 142 of adjacent pairs of ribs define individual food product receiving slots spanning width W of the interior cavity from the first side wall 128 to the second opposing sidewall 132. An individual food product receiving slot is typically designed for one food product but may be designed to accommodate one or more food products.

With specific respect to FIGS. 3A-3B, for each food contacting face 138, the food contacting face 138 is at an angle Θ₁ relative to the sidewall from which the rib extends. For each secondary contacting face 140, the face 140 is at an angle Θ₂ relative to the sidewall from which the rib extends. In one or more embodiments, Θ₁ is equal to Θ₂. In the embodiment of FIG. 3A, Θ₁ and Θ₂ are both about 72°. In the embodiment of FIG. 3B, Θ₁ and Θ₂ are both about 63°. Each rib has a height (“H”) which is the distance along the sidewall between the rib's food contacting face 138 and secondary face 140. In one or more embodiments, the H is ≥0.5 centimeters.

In one or more embodiments, the angle Θ₁ of the food contacting face relative to the sidewall is less than or 135° and greater than or equal to 45°. The range may be 135°≥Θ₁≥45° or 120°≥Θ₁≥60° or all values and or more embodiments, the angle Θ₂ of the secondary face relative to the sidewall is less than or 135° and greater than or equal to 45°. The range may be 135°≥Θ₂≥45° or 120°≥Θ₂≥60° or all values and subranges therebetween. In one or more embodiments, Θ₂ is about 90°. Moreover, the angles of Θ₁ and Θ₂ may be independent of one another.

With respect to the fluted edge 139, FIG. 4 provides exemplary shapes: “A” shows a chevron profile “B” shows a circle profile, “C” shows an arced rectangle profile, “D” shows a square profile, and E″ shows a rounded, square profile.

Turning to FIGS. 5-8, various angles of the faces of the ribs can be used. In FIG. 5, rib pair 2 a and 2 b are shown holding food product 150 that is in contact with a food contacting face of each rib. Between the secondary faces of ribs 1 a and 1 b and the food contacting faces of ribs 2 a and 2, are channels 10 a and 10 b, respectively. Channels 10 a and 10 b as they span across the tray width define an individual food product receiving slot. The angles of the food contacting faces of ribs 1 a,b and 2 a,b are approximately 45″. The angles of the secondary faces of ribs 1 a,b and 2 a,b are approximately 135°.

In FIG. 6, rib pair 4 a and 4 b are shown holding food product 150 that is in contact with a food contacting face of each rib. Between the secondary faces of ribs 3 a and 3 b and the food contacting faces of ribs 4 a and 4 b, are channels 12 a and 12 b, respectively. Channels 12 a and 12 b as they span across the tray width define an individual food product receiving slot. The angles of the food contacting faces of ribs 3 a,b and 3 a,b are approximately 135°. The angles of the secondary faces of ribs 3 a,b and 4 a,b are approximately 45°.

In FIG. 7, rib pair 6 a and 6 b are shown holding food product 150 that is in contact with a food contacting face of each rib. Between the secondary faces of ribs 5 a and 5 b and the food contacting faces of ribs 6 a and 6 b, are channels 14 a and 14 b, respectively. Channels 14 a and 14 b as they span across the tray width define an individual food product receiving slot. The angles of the food contacting faces of ribs 5 a,b and 6 a,b are approximately 90°. The angles of the secondary faces of ribs 5 a,b and 6 a,b are approximately 45°.

In FIG. 8, rib pair 8 a and 8 b are shown holding food product 150 that is in contact with a food contacting face of each rib. Between the secondary faces of ribs 7 a and 7 b and the food contacting faces of ribs 8 a and 8 b, are channels 16 a and 16 b, respectively. Channels 16 a and 18 b as they span across the tray width define an individual food product receiving slot. The angles of the food contacting faces of ribs 7 a,b and 8 a,b are approximately 45°. The angles of the secondary faces of ribs 7 a,b and 8 a,b are approximately 90°.

FIG. 9 is a cross-sectional view of the tray along line 9-9 of FIG. 3. The tray has a depth “D” of the interior cavity or sidewall. In one or more embodiments, D is 1-2 centimeters greater than the diameter or thickness of the product. In one or more embodiments, D is 1.1 to 3.0 times greater than the diameter or thickness of the product; and all values and subranges therebetween. Ribs 116 a and 116 b are shown with their fluted edges 139, which are at an angle α relative to the interior surface 124 of the base 122 of the tray. In this embodiment, α is about 90°. In one or more embodiments, 180°≥α≥90°.

FIG. 10 provides a perspective side view of a package 200 having two trays 204 joined together along edges of their respective flanges 237. A lidding film 202 is heat sealed to individually cover both interior cavities.

EXAMPLES Example 1

A tray having pairs of ribs was thermoformed and sausages were placed in the tray according to FIG. 11A, which is a top view, and FIG. 118, which is a side view. The tray of this example had a depth of about 4.55 cm. Individual ribs of a first set of ribs were sized to be ˜ 7% of the tray width; and Θ₁ and Θ₂ were both about 63°. Individual ribs of a second set of ribs were sized to be ˜14% of the tray width; and Θ₁ and Θ₂ were both about 72°. FIGS. 11A-B show the tray in a first position, which is a horizontal position on a table. Upon moving the tray into a second position being about 45° more upright than the first position as shown in FIGS. 12A-B, front and side views, the sausages are retained in individual food product receiving slots. Upon moving the tray into a third position being about 90″ more upright than the first position as shown in FIGS. 13A-B, front and side views, the sausages are retained in individual food product receiving slots. Therefore, the ribs of this example are sized to ensure the food product remains in place when tilting the tray.

Example 2 Comparative

A comparative tray having pairs of ribs was thermoformed and sausages were placed in the tray according to FIG. 14, which is a top view. All of the individual ribs were sized to be ˜3.5% of the tray width; and Θ₁ and Θ₂ were both about 60°. FIG. 14 shows the tray in a first position, which is a horizontal position on a table. Upon moving the tray into a second position being about 75° more upright than the first position as shown in FIGS. 15A-B, front and side views, the sausages were not retained in individual food product receiving slots. Therefore, the ribs of this example are not appropriately sized to ensure the food product remains in place when tilting the tray.

Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

Reference throughout this specification to “one embodiment,” “certain embodiments,” “one or more embodiments” or “an embodiment” means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Thus, the appearances of the phrases such as “in one or more embodiments,” “in certain embodiments,” “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily referring to the same embodiment of the invention. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents. 

What is claimed is:
 1. A formed tray for packing food products, the tray comprising: a base; a plurality of sidewalls integrally formed with and extending from the base, the base and sidewalls defining an interior cavity having a cavity width; a plurality of pairs of ribs integrally formed with and extending from first and second opposing sidewalls into the interior cavity, and a plurality of channels positioned between and separating adjacent ribs, wherein each channel of an adjacent pair of ribs defines an individual food product receiving slot.
 2. The formed tray of claim 1, wherein each rib extends into the interior cavity a length that is at least about 7% of the cavity width.
 3. The formed tray of claim 2, wherein the length that each rib extends into the interior cavity is at least about 10% of the cavity width.
 4. The formed tray of claim 3, wherein the length the each rib extends into the interior cavity is at least about 14% of the cavity width.
 5. The formed tray of claim 1, wherein each pair of ribs is effective to retain an individual food product in the individual food product receiving slot upon movement of the tray from a first position to a second position, the second position being greater than or equal to about 45° more uptight than the first position.
 6. The formed tray of claim 1, wherein each rib comprises a food contacting face, a secondary face opposing the food contacting face, and a fluted edge at an intersection of the food contacting and secondary faces.
 7. The formed tray of claim 6, wherein the fluted edge of each rib is disposed at an angle α relative to an interior surface of the base, and about 80°≥α≥90°.
 8. The formed tray of claim 6, wherein each food contacting face is disposed at an angle Θ₁ relative to the sidewall from which the rib extends and about 135°≥Θ₁≥45° and each secondary face is disposed at an angle Θ₂ relative to the sidewall from which the rib extends and about 135°≥Θ₂≥45°.
 9. The formed tray of claim 1, wherein the interior cavity has a depth “D” that is 1.1 to 3.0 times greater than a diameter or thickness of an individual food product.
 10. The formed tray of claim 1 further comprising third and fourth opposing sidewalls.
 11. A formed tray for packing food products, the tray comprising: a base; a plurality of sidewalls integrally formed with, and extending from the base, the base and sidewalls defining an interior cavity having a cavity width, the plurality of sidewalls comprising first and second sets of opposing sidewalls; a plurality of pairs of ribs integrally formed with and extending from the first set of opposing sidewalls into the interior cavity, and a plurality of channels positioned between and separating adjacent ribs, wherein each channel of adjacent pairs of ribs defines an individual food product receiving slot; wherein each rib comprises a food contacting face, a secondary face opposing the food contacting face, and a fluted edge at an intersection of the food contacting and secondary faces.
 12. The formed tray of claim 11, wherein each rib extends into the interior cavity a length that is at least about 7% of the cavity width.
 13. The formed tray of claim 11, wherein each food contacting face is disposed at an angle Θ₁ relative to the sidewall from which the rib extends and about 135°≥Θ₁≥45° and each secondary face is disposed at an angle Θ₂ relative to the sidewall from which the rib extends and about 135°≥Θ₂≥45°.
 14. A food package comprising: one or more formed trays of claim 1; and a lidding film sealing food products in the interior cavity by a heat seal.
 15. The food package of claim 14, wherein the food products are elongate.
 16. The food package of claim 15, wherein the food products are cylindrically-shaped.
 17. The food package of claim 14 comprising two formed trays joined along edges of flanges of the trays.
 18. A method of packaging food comprising: thermoforming a tray according to claim 1; and sealing foods in the interior cavity of the tray with a lidding film.
 19. A method of displaying food products comprising: obtaining the food package of claim 14; and tilting the package from a first position to a second position, the second position being greater than or equal to about 45° more upright than the first position.
 20. The method of claim 19, wherein individual food products are retained in the individual food product receiving slots upon tilting. 